For many purposes, fiber optics provide superior signal transmission to electrical signal transmission. Fiber optic elements are particularly useful for transmitting distortion-free signals over short or intermediate distances in locations where the concentration of electrical transmission is substantial creating significant electrical flux that interferes with good electrical signal transmission.
In order to carry the amount of information necessary in many types of data transmission, multifiber optical cable is frequently used in optical transmission systems. At the cable terminus, the individual fibers are "broken out" of the cable, that is freed from the outer jacket, and terminated by connecting them to light signal producing apparatus, e.g., light emitting diodes, or optical detectors.
A typical multifiber cable contains an outer jacket of polymeric material, such as polyvinyl chloride, a central strengthening member, and a plurality of buffer tubes surrounding the strengthening member in which the optical fibers are loosely retained. In a typical termination of a multifiber cable, the outer jacket is cut away to allow the buffer tube-protected fibers to be separately connected to optical transmitting or receiving units. The end of each buffer tube is cut back, and the ends of the optical fiber and cut-back buffer tubes are inserted and glued into connectors. The ends of the fibers are polished by conventional means, and the connectors are mated with alignment sleeves which hold the polished optical fiber ends closely adjacent to the optical detecting or transmitting units or in close proximity to the end of a similar optical fiber. The adhesion of the optical fibers to the connectors provided by the glue, e.g., epoxy, is relatively weak, typically providing only about five pounds of pull-out strength. Where human activity is considerable at the breakout location, the fibers may be inadvertantly dislodged from the fitting. Even if the fiber is not dislodged, jarring of an optical fiber held only by glue may introduce noise in the optical signal. There exists a need for improved breakouts and terminations for multifiber optical cable.